python中threading怎么开启关闭线程

import inspect
import ctypes
def _async_raise(tid, exctype):
  """raises the exception, performs cleanup if needed"""
  tid = ctypes.c_long(tid)
  if not inspect.isclass(exctype):
    exctype = type(exctype)
  res = ctypes.pythonapi.PyThreadState_SetAsyncExc(tid, ctypes.py_object(exctype))
  if res == 0:
    raise ValueError("invalid thread id")
  elif res != 1:
    # """if it returns a number greater than one, you're in trouble,
    # and you should call it again with exc=NULL to revert the effect"""
    ctypes.pythonapi.PyThreadState_SetAsyncExc(tid, None)
    raise SystemError("PyThreadState_SetAsyncExc failed")
def stop_thread(thread):
  _async_raise(thread.ident, SystemExit)

import threading
import time
class MyThread(threading.Thread):
  def __init__(self):
    threading.Thread.__init__(self)
    self.Flag=True        #停止标志位
    self.Parm=0         #用来被外部访问的
    #自行添加参数
  
  def run(self):
    while(True):
      if(not self.Flag):
        break
      else:
        time.sleep(2)
  
  def setFlag(self,parm):     #外部停止线程的操作函数
    self.Flag=parm #boolean
 
  def setParm(self,parm):     #外部修改内部信息函数
    self.Parm=parm
 
  def getParm(self):       #外部获得内部信息函数
    return self.Parm
 
 
if __name__=="__main__":
  testThread=MyThread()
  testThread.setDaemon(True)     #设为保护线程，主进程结束会关闭线程
  testThread.getParm()      #获得线程内部值
  testThread.setParm(1)      #修改线程内部值
  testThread.start()       #开始线程
  print(testThread.getParm())    #输出内部信息
  time.sleep(2)          #主进程休眠 2 秒
  testThread.setFlag(False)      #修改线程运行状态
  time.sleep(2)          #2019.04.25 修改
  print(testThread.is_alive())  #查看线程运行状态

def __init__(self):
    self.Flag=True        #停止标志位
    self.Parm=0         #用来被外部访问的
    #自行添加参数

def __init__(self):
    threading.Thread.__init__(self)
    self.Flag=True        #停止标志位
    self.Parm=0         #用来被外部访问的
    #自行添加参数